"Firefox 4's Jaegermonkey javascript engine will just about match Chrome's V8 javascript engine, and Firefox 4 will support hardware accelerated page rendering and compositing, which will outperform Chrome's rendering speeds by many times over.

I believe it when I see it. Don't get me wrong, I really hope this will be the case but judging from some nightlies I really do not have much hope in that. I have to try a fresh nightly, though. Oh and I use Firefox. I only use Chrome when some site is just to horrible slow with Firefox (e.g. when browsing a very long archive on tumblr Firefox sometimes gets so slow it needs >15 seconds to react after each click). "

The nightlies are sometimes a bit of pot luck, in that it is possible to get regressions.

I run the latest Chrome and Firefox 4 nightlies side by side on the same system each and every day. Some days Chrome is way faster, and other days (depending on the nigthly build), there is no perceptible difference in speed at all.

As it always has done, from an end user point of view, Firefox and its extensions still maintains an appreciable edge in functionality over Chrome, no matter the speed.

Also, if you are running Linux, you might consider running Chromium instead of Chrome, since Chromium does not send any of your browsing metrics type of data back to Google as Chrome does.

Finally, because different browsers optimise javascript differently, so speed comparisons can easily go different ways. For example ... the V8 javascript benchmark is called "V8" because it is actually named after Chrome's javascript engine. If you want another benchmark that isn't set up to show off the performance of Chrome's V8 javascript engine in particular, here is a new one that you might trial: